Pot And Psychosis: Possible Link?

Pot And Psychosis: Possible Link?
Posted by CN Staff on July 26, 2007 at 17:50:58 PT
By Kathleen Doheny
Source: WebMD 
WebMD -- Smoking cannabis, or marijuana, as a youth could boost the risk of developing a psychotic illness later in life by about 40%, according to a new analysis of published studies conducted by British researchers. The more than 40% increase in risk applies to those who have ever used the drug, and the risk rises even more with frequent use, according to Stanley Zammit, M.D., Ph.D., clinical lecturer in psychiatric epidemiology at Cardiff University and the University of Bristol in the U.K., a study co-author.
"People who have ever used cannabis, on average, have about a 40% increased risk of developing psychotic illness later in life compared with people who have never used cannabis," he tells WebMD. "People who used it on a weekly or daily basis had about a 100% increased risk, or twofold." Even so, he adds, "the risk is still relatively low." But as Zammit and his colleagues note in the new report, scheduled to appear in the July 28 issue of The Lancet, there is enough evidence of a marijuana-psychosis link that they believe policymakers need to provide the public with information. The report drew protests and skepticism from representatives of The National Organization for the Reform of Marijuana Laws, who questioned the validity of the findings. Zammit and his colleagues pooled the results of 35 published studies on marijuana use and mental health effects, including psychotic effects such as schizophrenia (in which people may hear voices or hallucinate) or affective problems such as depression and anxiety. They analyzed the results of all the studies, a method known as a meta-analysis. The increased risk of psychosis with marijuana use persists, Zammit's team found, independently of the transient intoxication effects of the drug and independently of what they call "confounding factors," such as existing mental health problems or other drug use. "We can't be sure it is causal," he says of the association. "[But] studies find an association rather consistently." Still, he tells WebMD, "It's always possible people who use cannabis may be different [in some way] than those who don't." The researchers also looked at the association between marijuana use and depression and anxiety but found that the evidence is "less strong than for psychosis but is still of concern." In the U.S., marijuana is the most widely used of various illicit drugs, according to the University of Michigan Monitoring the Future Survey. About 6.8% of middle school and high school students used marijuana in 2005, down from 7.6% the previous year, according to the annual National Survey on Drug Use and Health, a federal report. In the U.K., Zammit estimates, about 15% of youths aged 16 to 24 say they use cannabis on a monthly basis. In an accompanying comment, two scientists from Copenhagen University Hospital echo Zammit's belief that "there is a need to warn the public of these dangers, as well as to establish treatment to help young, frequent cannabis users." In an editorial in the same issue, Lancet editors note that the publication ran an oft-quoted editorial in a 1995 issue stating that "the smoking of cannabis, even long term, is not harmful to health." Now, the editors note, research published in the interim, including the meta-analysis, has triggered a change in their thinking, with them now stating that cannabis use "could increase the risk of psychotic illness" and that more research is needed on any link with depression and anxiety. If the association exists between marijuana use and psychotic illness, "we would have seen the negative effects they were warning about if they were significant," says Paul Armentano, a senior policy analyst for the National Organization for the Reform of Marijuana Laws (NORML), based in Washington. Most Western cultures, he tells WebMD, have witnessed "an explosion among marijuana use among adults and young people. "Where is the explosion in cannabis-related mental illness?" he asks. "The paper says, 'You are right, we haven't seen it. Maybe it is a delayed reaction.'" Armentano argues the rise in mental illness would have already occurred if the link exists. Armentano also wonders if the psychosis may have come first, before the marijuana use, for some people. In the paper, the authors note that such reverse causation is not likely for psychosis but that the studies of marijuana and depression did not adequately address the possibility of reverse causation. Politics in the U.K. may be driving the effort to analyze an association between marijuana and mental illness, Armentano tells WebMD. Prime Minister Gordon Brown has been quoted in the British press as saying he has never used cannabis, even as cabinet ministers tell about their cannabis-filled younger days. In 2004, the U.K. downgraded cannabis to a class C drug, reducing penalties for possession, production, and supply. Now, the Advisory Council on the Misuse of Drugs in the U.K. will look at evidence for harms caused by cannabis and discuss whether the drug should be relabeled, perhaps as a class B drug of misuse, with stiffer penalties for possession. "The article is worth paying attention to," Bruce Spring, M.D., an assistant professor of clinical psychiatry at the University of Southern California Keck School of Medicine, Los Angeles, an expert familiar with the study but not involved in it. "It certainly gives cause for concern," Spring says of the findings about marijuana and psychosis risks. Still, he says, the overall risk is relatively low, statistically speaking. "In general, the overall risk of someone getting a psychotic illness is about 3%," he says. "Now what this study is saying is that that 3% risk is increased by 40% [or more]," he says. So the risk with marijuana use would rise to 4.2%. Put another way: In a group of 100 people, three would be expected, statistically speaking, to develop a psychotic illness such as schizophrenia or bipolar disorder with psychosis. "When you factor in the marijuana study, one or two more, depending on how often they use it, will have psychotic illness," Spring says. Says Spring, "I would tell people there is now some pretty good evidence that smoking marijuana can have some harmful consequences, and they are putting their future well-being at risk [if they smoke marijuana]. The more you smoke, the greater the risk, according to this study." Zammit, the study co-author, adds, "I think the important message is to be aware of these risks." Those who have other risk factors for psychotic illness, such as a family history, might want to pay closer attention, he tells WebMD. Quote: "We can't be sure it is causal ... [But] studies find an association rather consistently." Note: British Studies Show Marijuana Use May Raise Risk Of Psychotic Illness Risk By 40%.Reviewed by Louise ChangSource: WebMD (US)Author: Kathleen DohenyPublished: July 26, 2007 Copyright: 2007 WebMD Inc.Contact: Sswint Website: -- Cannabis Archives
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Comment #22 posted by NikoKun on July 30, 2007 at 08:34:11 PT
The link isn't real.
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Comment #21 posted by jimijaymz on July 29, 2007 at 08:27:50 PT:
deep rest
it seems curious ,in a laughable sort of way, that the very thing causing deep-ression is lack of deep-rest. many cannabis user report the rest they experience as the deepest, most gratifying of their life. could the deep-ression, schizo reaction be fueled by the fact that IT IS ILLEGAL TO USE ??? what a shock to discover that the harm done by drugs is actually the legislation aimed at filling more prisons, not the drugs themselves. these things aren't revelation to those of us familiar with big pharma. if it wasn't for anti-deep-ressants / statins , where would those folks turn for their cash ? can't be weed, you can't patent something that will grow in the cracks of the sidewalk and has been used by man since anybody wrote / drew anything. know acception. peace. 
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Comment #20 posted by afterburner on July 28, 2007 at 08:58:47 PT
paul armentano #16 
Rightt on Paul. I noticed that "meta-analysis" right away. However, local papers just reported "a new study" without any details or citations. Irresponsible scare journalism!
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Comment #19 posted by Hope on July 28, 2007 at 06:59:35 PT
Pot And Psychosis
There is a terrible link between pot and psychosis.The psychotics are the people who hate, punish, and fear those who would dare to consume or handle pot.The punitive prohibs really are nuts...dangerous, mean, hateful nuts. They've lost touch with reality every bit as much as the witch killers in Salem did.Reality? Punishing, hurting, even killing people like they do to prevent them from using the herb is truly and definitely psychotic. And the fact that the prohibitionists avoid that reality, that truth...just adds to the terrible fact of their true psychosis. They refuse to see the reality of the situation. The prohibitionists are truly insane and it becomes clearer every day.So yes...there certainly is a link between pot and psychosis. I've seen the true psychos, the prohibitionists, for what they are. Brrrrr.
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Comment #18 posted by Hope on July 27, 2007 at 21:21:07 PT
These sorts of handy, dandy "Studies"
give the term "Political Science" an entirely new meaning.
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Comment #17 posted by cannabliss on July 27, 2007 at 15:08:43 PT
Healthy Skepticism
Here are a few rules of thumb when reading press reports on "scientific" studies. Some of this comes from personal experience working in various scientific and pseudo-scientific environments.1 - The further away a discipline is from engineering science, the more BS is likely to creep in. Think about a study on whether a material was suitable for in auto-manufacturing. You can run crash tests, durability tests, whatever, very easily repeatable, to determine the validity of claims.On the other hand, sciences such as nutrition and psychology have less clear repeatable results. Is soy good or bad? How much fat should you eat? How does one repeat these experiments and control for all the myriad factors in human physiology or psychology? Therefore, any claims made by a study (this wasnt even a study, it was a "meta-study") can be flat-out wrong, but nobody can really prove it, since so many other factors are always at work.2 - Beware of politically charged studies. Every (so-called) scientist I've ever dealt with had ego issues and always had a bias. If you read that blueberries are a wonder-food, that's probably not a political issue (though if the blueberry growers' association sponsored the study, maybe it is). On the other hand, something like cannabis is clearly a political issue, so you have to be skeptical (that goes for "pro" as well as "con"). One person I knew was studying the 'health effects' of guns. Of course, he was out to prove guns were bad and could do so by saying that suicide is a negative health effect of gun ownership. Of course, he never allowed that self-defense from a criminal might be a life-extending health benefit of guns, so his data were hopelessly biased. If you want to write an op-ed pro or against an issue, go ahead, but don't wrap it in a thin veneer of pseudo-science.3 - Even discounting bias and complexity of systems, don't discount plain old human error. I reviewed a study where someone had forgotten to convert hours to minutes in a calculation so everything was off by 60x (!). The problem again is, how would you know. If they make critical errors, where is the obvious effect of the error (such as, say, a plane dropping out of the sky if a physicist forgot to carry the one).4 - Don't overestimate the intelligence of journalists. Few have any understanding of math or science and it seems fewer have a healthy sense of skepticism anymore ("WMD in Iraq" comes to mind). In this report, they talk about "any use". I'm supposed to believe that one bong hit at a party at age 17 leads to a lifetime +40% risk of psychosis? That is beyond absurd. Almost every media report of this kind leaves out critical details and omits follow-up questions.I could go on, but you get the idea. Ask yourself - how many pot users have you known? How many alcohol users have you known? How would you compare the effects? How many violent or felonious activities were committed by people you know under the influence of alcohol vs. pot? Don't let statistical game-playing interfere with (un)common sense.
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Comment #16 posted by paul armentano on July 27, 2007 at 14:27:34 PT
Pot and Mental Illness
Despite the screaming headlines, this is much ado about nothing. This was meta-analysis — in other words, a review of existing science that’s been out there for years. The primary reason this is getting play now is because the Gordon administration wants to override the former Blair gov and reschedule cannabis from Class C to B (so that police can arrest, rather than cite, users). The ACMD (Advisory Council on the Misuse of Drugs) in the UK reviewed this same data just two years ago and found any association b/n pot and mental illness to be “weak.” See:
sSheet=/news/2006/01/20/ixhome.html In addition, even the authors admit that not parallel rise in marijuana-associated mental illness has yet to occur in cultures that have had dramatic rises in pot use. Since many mental illnesses such as schizophrenia generally present themselves at young ages (20s), this reality would seem to discredit any strong causal relationship.
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Comment #15 posted by WolfgangWylde on July 27, 2007 at 13:22:42 PT
What's good for the goose...
(Tobacco) Smoking may be cause of mental illness
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Comment #14 posted by observer on July 27, 2007 at 12:15:15 PT
re: disclaimer never mentioned
Thanks for pointing that out, greenmed."The research was funded by the U.K. Department of Health. Two co-authors were invited experts on the government’s Advisory Council on the Misuse of Drugs Cannabis Review in 2005; some co-authors received research money or other fees from pharmaceutical companies, including consultation on antipsychotic medication."How interesting. I notice a huge media campaign whenever anyone says anything that might be "bad" about pot. Hundreds of articles that scream "Pot Makes You Pcycho!", here: (7/27/2007) how many of those mentioned that disclaimer? This is another bought-and-paid-for "Pot is Bad Says Science" propaganda report. You can be sure this one will fall apart like a house of cards, just as all the others have. It boils down to this: people who are schizophrenic like to smoke pot (statistically) a bit more than people who aren't schizophrenic. They also like to smoke cigarettes more than people who aren't schizophrenic. (Etc.) Few today claim that tobacco leads to insanity. Though to be sure, 'officials' and 'authorities' in the past repeatedly claimed tobacco made people insane. Here's an example from the 1920s.
Fifty percent of our insanity is inherited from parents who were users of tobacco; sometimes the victim is a smoker himself, which hastens it on. Thirty percent of insanity cases are caused directly from cigarette smoking and the use of tobacco. 
(Ray, O.S. Drugs, Society and Human Behavior, St. Louis: C. V. Mosby, 1972, p. 100, from )
The trick is an ancient one.Cause and Effect. The propagandists that tell you pot "causes" this or that, they are outright lying. The more shrewd propagandists know this, and will merely insinuate cannabis causes this or that bad thing, but he won't say that it does for sure, exactly. He'll let the naive listener make and repeat that leap. 
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Comment #13 posted by Richard Zuckerman on July 27, 2007 at 07:48:20 PT:
Dr. Lester Grinspoon's book entitled "MARIHUANA RECONSIDERED" says you should consider whether other factors caused the problems, whether the problems were pre-existing. I am one example to be considered. My father died when I was 12 years young. I was introduced to smoking Cannabis at 16 years young. Yet, I worked out with weights, was as strong and athletic as most of the people in the neighborhood. At around the time George Herbert Walker Bush rose to power, around 1980, the drug war escalated, leading to my arrest and ignorant pleas of guilty for under 25 grams "Marijuana" possession, which they used to deny me a permit to purchase a firearm. I was railroaded for psychiatric "treatment" a number of times, with "Cannabis abuse" being one of their diagnoses, by "defense" attorneys who were paternalistic rather than zealous advocates for the defense. Now I am faced with the stigma of "mental illness", "drug offender", convicted felon, while American people vote for GOP politicans more interested in "free trade" agreements, open-border immigration, the war on Cannabis, a police state. Less than a month ago, an article was posted on, supported by official warnings of economic problems, and describing the lastest developments in the theft of the $4.5 Trillion Wanta Plan Settlement by Vice President Dick Cheney and U.S. Treasury Secretary Henry Paulson as a SERIOUS THREAT upon our economy. I guess we'll get another 2% of the American population voting for 3rd parties. The other day, I ordered a shirt and 10 bumper stickers for I already have a bumper sticker on my car bumper! Obama ain't good enough!I have 17 days in which to submit a petition to the New Jersey Supreme Court asking whether Heck v. Humphrey requires a municipal court conviction to be vacated as a precondition to a lawsuit alleging violation of the 1947 New Jersey Constitution, in light of New Jersey Rule of Evidence 803(c)(22), Trisuzzi v. Tabatchnik, 285 N.J.Super. 15, 25, 666 A.2d 543 (App. Div. 1995); Olivieri v. Y.M.F. Carpet, Inc., N.J.  (2006)(Collater estoppel will not be applied if it would be unfair to do so or if the procedures used in the prior decision were not the same); Doe v. Poritz, N.J.  (1997)(The doctrine of Fundamental Fairness). It will cost me time and money, especially $300 deposit to New Jersey's highest court.
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Comment #12 posted by unkat27 on July 27, 2007 at 05:28:07 PT
More Propaganda designed to Persecute
Now, based upon this BS, if and whenever cannabis users decide to stand up and defend themselves against the violent force of prohibitionists (DEA fascists, dumbed-down cops) they will be able to label them "psychotic" and make the dumbed-down public believe that violating and taking away their rights is okay for the safety of the children and the public in general. After all, we can't have "violent psychotics" running around free, can we?Wonder when they'll spin the "psychotic" into someone prone to violent behavior? Funny, my step-father was like that for most of my youth, but he didn't use cannabis, he abused alcohol.This war will never end, becuz the propaganda defeats the defense. Pacific attitudes are ignored while violent attitudes are demonized completely and punished absolutely. Cannabis users will never have free reign in this reality. The fascists own it, lock, stock, and barrel.
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Comment #11 posted by HempWorld on July 26, 2007 at 22:18:29 PT
How do you spell, smokescreen...
Oh yeah, Psychosis... but somehow marijuana users do not show up in the death or violent death, for that matter, statistics... Marijuana deaths in the last say 10,000 years: 0. Ok, so we have a real 'problem' here... not! Whatever it takes... paid for by the pharmaceutical industry. Mmm... ok, I get it...Smoke and mirrors, the next disaster is always just around the corner. Except that the FACTS do not bear this out for 70 years and counting...
Nobody can stop this!
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Comment #10 posted by John Tyler on July 26, 2007 at 21:30:24 PT
seen this before
Lets see the new Prime Minister of England wants to make cannabis law more restrictive for one reason or another. He has to have a reason to sell this idea to the public. He tells his operatives to have some doctor or something come up with a “scientific” study that says cannabis makes you crazy, even if it is misleading and not exactly true. Make it long and fuzzy and fill it with boring jargon so most people won’t read all of it anyway. Get it published. Then he can say, this new study says that cannabis makes you crazy so we have to make it more restrictive. Parliament goes along with it only to realize later if ever that they have been duped again. Before the drumbeat on this thing gets too loud you have to think about it, something politicians don’t seem to do, and say, millions of people have been using cannabis for going on forty years now. Where are all of the so-called mentally ill cannabis users? While we are on the subject of mental illness, what about the link between alcohol abuse and physical and mental illness. If the Prime Minister is so interested in the welfare of the public he should have a study to check out alcohol and tobacco. I think those substances are a lot more troublesome, health wise than people using a little bit of cannabis. 
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Comment #9 posted by MikeEEEEE on July 26, 2007 at 21:17:48 PT
In the land of prohibition
Common sense is not common.
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Comment #8 posted by DjLoTi on July 26, 2007 at 20:31:21 PT
Possible link?
Alcohol and hardships, kidney failure, liver failure, brain damage, death? I dunno, what do you guys think? Possible link?
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Comment #7 posted by freewillks on July 26, 2007 at 19:39:31 PT
Fox news
Two of the authors of the study were invited experts on the Advisory Council on the Misuse of Drugs Cannabis Review in 2005. Several authors reported being paid to attend drug company-sponsored meetings related to marijuana, and one received consulting fees from companies that make antipsychotic medications.,2933,291043,00.html
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Comment #6 posted by Hope on July 26, 2007 at 19:37:35 PT
Pot may hike risk of psychosis, research finds a poll...asking whether you believe it or not.
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Comment #5 posted by FoM on July 26, 2007 at 19:08:41 PT
So very true. 
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Comment #4 posted by museman on July 26, 2007 at 19:03:26 PT
"Psychosis is a generic psychiatric term for a mental state often described as involving a "loss of contact with reality". " Politics, economics, religion, society in general. Man do we got problems.No reality to be found, just one mental invention after another.Have another hit of fresh air -if you can find it.
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Comment #3 posted by mayan on July 26, 2007 at 18:28:13 PT
I guess if we supported false flag terror attacks,illegal wars,stolen elections,etc. we would be perfectly sane!THE WAY OUT IS THE WAY IN...Rowe Arrested Despite Honorable Discharge Papers: Korey Rowe: "I'm Not Going Anywhere: Video E-mail to the Media and Truth Squad action in Texas (video):
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Comment #2 posted by FoM on July 26, 2007 at 18:23:03 PT
Thank you. They didn't have that information on the link I used.
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Comment #1 posted by greenmed on July 26, 2007 at 18:09:08 PT
"The research was funded by the U.K. Department of Health. Two co-authors were invited experts on the government’s Advisory Council on the Misuse of Drugs Cannabis Review in 2005; some co-authors received research money or other fees from pharmaceutical companies, including consultation on antipsychotic medication."
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